1. Field of the Invention
The present invention relates to novel optically active maleimide derivatives, optically active polymaleimide derivatives, production method and use thereof. Optically active polymaleimide derivatives are expected to find application as a separating agent for separating optically active compounds.
2. Description of the Prior Art
Shown below are a) optically active maleimide derivatives and b) optically active polymaleimide derivatives of the present invention:
(a) optically active maleimide derivatives. The compounds are represented by general formula (1) or (2): 
wherein R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, and R11 are each independently selected from the group consisting of hydrogen, methyl, ethyl, a straight-chained or branched alkyl having 3 to 10 carbon atoms and a straight-chained or branched alkoxy having 3 to 10 carbon atoms; and R12 is selected from the group consisting of methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, tert-butyl, methoxymethyl, ethoxymethyl and ethoxyethyl.
(b) optically active polymaleimide derivatives. The polymers are represented by the following general formula (3) or (4): 
wherein R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, and R11, are each independently selected from the group consisting of hydrogen, methyl, ethyl, a straight-chained or branched alkyl having 3 to 10 carbon atoms and a straight-chained or branched alkoxy having 3 to 10 carbon atoms; R12 is selected from the group consisting of methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, tert-butyl, methoxymethyl, ethoxymethyl and ethoxyethyl; n is an integer from 2 to 10000; and an asterisk represents an asymmetric carbon.
None of these compounds has been known to date, nor has any proposal been made to use these compounds as a separating agent for separating optical isomers.
Many optically active synthetic polymers that can be used as optical resolution agents are known, including optically active poly(triphenylmethyl methacrylate) disclosed in Japanese Patent Laid-Open Publication No. Sho 56-106907, optically active polyacrylamide disclosed in Japanese Patent Laid-Open Publication No. Sho 56-167708, and polyacrylamide disclosed in Japanese Patent Laid-Open Publication No. Sho 63-14446, which has a side chain including an optically active substituent and chemically bound to silica gel surfaces.
Despite the relatively high resolution that these optically active polymers can achieve when applied to separate certain types of optically active compounds, the polymers can be applied only to a limited range of racemic mixtures. For this reason, a need exists for novel polymers that have a wide range of applicability and specific performance.
Further, advancement in technologies and instruments for analysis has given rise to a demand for separating agents with a higher resolution.
In an effort to develop a novel separating agent capable of separating optical isomers at high resolution, the present inventors have discovered novel optically active maleimide derivatives as shown by the general formulae (1) and (2) above and novel optically active polymaleimide derivatives as shown by the general formulae (3) and (4) above that can be prepared by allowing the optically active maleimide derivatives to undergo asymmetric anionic polymerization, and found that these polymaleimide derivatives can serve as highly effective separating agents for separating optical isomers.
Accordingly, the present invention provides optically active maleimide derivatives of the general formulae (1) and (2), optically active polymaleimide derivatives of the general formulae (3) and (4), production methods of optically active polymaleimide derivatives of the general formulae (3) and (4), and use of optically active polymaleimide derivatives of the general formulae (3) and (4).